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#221
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Screw them iPods!!!
cuhulin |
#222
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In article , craigm
wrote: Telamon wrote: In article , craigm wrote: Tom Wells wrote: Thank you for explaining the mysteries of modulation byproducts and bandwidth in a way that makes the truth clear for people who may not have had radio schooling. Instead of making it sound harder than it really is.. The saddest part of it all is that MOST of the digihash flamethrower noise is describing to the demodulator that no modulation is present for most audio frequencies. Even if NO audio is present, the IBOC signal is still 45khz wide, The bandwidth used by IBOC is 30 kHz, not 45. describing each and every one of the possible audio passband frequencies as 0% modulation. Instead of just letting there BE no modulation, they've decided it's much better to have all these little subcarriers elaborately screaming "NO MODULATION AT 1200HZ!" "NO MODULATION AT 1201 HZ!", etc. It's like having a thousand people in a There is not a carrier for each discrete frequency. room screaming about nothing. In proper engineering, like with good manners, if you have nothing to say, you keep your mouth shut. You need to better understand the modulation method and how digital decoders work. Telamon wrote: snip This is a simple concept that many people don't seem to get. Information rate directly correlates to bandwidth in this way, higher rate and more detail means larger bandwidth. Analog or digital is just a method of encoding information. Narrow filtered analog is similar to low rate digital. It does not matter what digital method you use you can't get around the fact that a better picture or audio means you need to use more bandwidth. Oh, but it does matter. The choice if digital modulation and compression change things. For a given modulation method and compression scheme, what you say is valid. More content means more mandwidth. However, different modulation methods and compressions schemes result in differing bandwidth requirements for the same amount of content. If this isn't true, then PC modems would still be running at 1200 baud. One reason newer PC modems have higher baud rate it that they use more bandwidth than the old ones did. PC modems are limited by the bandwidth of the phone line. Well, since the phone line is the medium that the information goes through that is true but older modems did not use all that was available and the newer transmission schemes used more of that available bandwidth. I'm sorry but there is a direct correlation between bandwidth and information that can not be changed. Compression methods are not some kind of black magic that can stuff more information in the same number of bits. Compression methods can cause a digitized description of analog information to be more efficient and some methods are better than others but that is it. An example would be a picture of a checker board could be described with fewer bits because there is not that much information but change that to a wide view of scenery where every bit is more random and it can't be compressed to any extent. Compression can not cause a better "digital description" using the same bandwidth to occur as analog representation of the same. To be abundantly clear here my point is that DRM can not sound better than analog in the same bandwidth. There is more then one way to encode the analog world into digital and back and some methods are more efficient then others but there is no magic digital encoding system comprised of one or a combination of encoding methods that will magically stuff more information into the same bandwidth. The DRM controversy has gone on for a long time where the claim that DRM sounds better then analog in the same bandwidth. This is a bunch of BS. Not only does this violate the laws of physics it further makes less sense from the standpoint of conversion of analog to digital at the transmit end and then digital back to analog at the receive end. Technically changing from analog to digital and back introduces conversion errors so DRM in the same bandwidth has to sound worse than analog. The only way DRM can sound better is to use more bandwidth than analog. You are completely ingoring compression and modulation methods. Yeah, it is not germane to what I wrote. Yes, converting analog to digital then back to analog will degrade the analog signal. A straight wire is always better. However AM, radio is not a straight wire. This is all a given. With AM radio, an analog signal is compressed, band width limited, converted to electromagnetic waves, mixed with any other waves on the same frequency between transmitter and receiver, converted to an electrical signal, passed through an IF that further bandwidth limits the signal, and then run through a detector that usually adds at least 1% distortion. Now you are bring other issues into the picture. I want to ignore these issues also. So there are are two basic concepts for anyone reading the news group. DRM and IBOC claims are a bunch of BS. Analog or any digital system will sound better the more bandwidth you use. I can compress audio to a 64 kbps data rate for an iPod. This sounds better than _any_ AM broadcast I have ever heard. Better signal to noise, lower distortion, better audio bandwidth and stereo. I've also heard FM band IBOC, and I will say that it did sound better than the analog channel. However this may have been due to significant amounts of signal processing at one end of the chain or the other. Music from an Ipod is not short wave analog or DRM. The point of my post is to dispel the notion that DRM can sound better in the same bandwidth space as an analog signal and the basic theory behind the reasoning, it can not regardless of the compression algorithms and modulation scheme. The encoding method for iPod and DRM and both forms of AAC. My point is that it is possible for DRM to be an improvement. Point not taken. Sure it is possible for DRM to sound better than analog for similar reasons analog can sound better than DRM. The underlying concept is a higher information rate translates to a higher quality picture or sound in real time. Just so my point in posting originally is not lost DRM started out and still tries to claim it is an improvement over analog. This claim of being "better" was to use the same spectral space. This is an incorrect notion, period. It does not matter what the modulation mode, compression or combination of compression algorithms are used, bandwidth determines the amount of information can be transmitted over time. If DRM is to sound "better" then a current analog signal it must occupy more bandwidth than the analog signal so more information can be transmitted over time. If the analog information you want to transmit is low detail and quality to start out with a compression scheme can give the "appearance" that more information is being transmitted over time but it is not. With compression it is possible to transmit low quality at a higher rate or say two low quality streams at the same rate but this is not the same thing as a higher data rate being transmitted. Digitization and compression can give you more options trading off quality and quantity but it can not magically stuff a higher data rate of information in the same bandwidth. This is basic information transmission theory. Look it up. (And no, I have no desire for IBOC on the AM broadcast band. I think there are too many associated issues, the primary one being the consumption of 30 kHz bandwidth. IBOC on FM may work and be viable in the long run. I'm not either. At the least they should split the existing band between IBOC and better would be another band. I am in favor of DRM.) I'm not. -- Telamon Ventura, California |
#223
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#224
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Let me twist that tuning knob around on the radio I bought from Bian.
www.us963.com Jacksonnnnnnnn,,,,, Country Western Music. Where God isn't dead. cuhulin |
#225
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My phone number is 601 073 9733.You can't phone me because I keep my
phone Unplugged all the time excpt when I want to use it.Go ahead,try to phone me.Wimmins,email me and tell me to plug my phone in. cuhulin |
#226
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Mark Zenier wrote:
In article , D Peter Maus wrote: Mark Zenier wrote: And pretty soon, somebody will have a radio with Tivo like features for $39.95 that records several (or all of the available) stations and has fast forward buttons so that no one will ever need to listen to a commercial. And then what happens to your business? Actually, the latest versions of TiVo and it's clones now are starting to display popup advertisements when the user attempts to fastforward through the commercials. And Tivo, as a company is now (or soon to be) roadkill. First, the cable set top box manufacturers are duplicating their boxes' functions. And anybody but the brain dead will think twice or three times to buying a box that requires a subscription, a phone line, and will snitch on you about every time you did a rewind to get another look at a good cleavage shot. The primary reasons I never got a TiVo. And now this. They really needed to figure out who their customers are. Truth is: Most people don't care about the cost, the privacy invasion, or even the use of the phone. They care about features, and convenience. Which goes a long way to explaining why TiVo boxes are being replaced with Cable boxes with TiVo features. Many of which are actually TiVo boxes in cable clothing. |
#227
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![]() "D Peter Maus" wrote in message ... Mark Zenier wrote: In article , D Peter Maus wrote: ¿ And anybody but the brain dead will think twice or three times to buying a box that requires a subscription, a phone line, and will snitch on you about every time you did a rewind to get another look at a good cleavage shot. The primary reasons I never got a TiVo. Once you have on, and I have had them since the first year... something like 7 or 8 years ago... and could not lieve without one. I hve three different ones in the house. And now this. They really needed to figure out who their customers are. Truth is: Most people don't care about the cost, the privacy invasion, or even the use of the phone. They care about features, and convenience. Which goes a long way to explaining why TiVo boxes are being replaced with Cable boxes with TiVo features. Many of which are actually TiVo boxes in cable clothing. I have a cable "equivalent" at my weekned place. It is hateful in every aspect (Time Warner) from the awful software to the remote control to the highly inaccurate listings of upcoming progframs. I am swiutching to Direct TV and a TIVO sometime this year when I can be there on a weekday to meet the installer. A friend who moved to an apartment where he could not get Direct TV had to use cable for a year. He said one of the main reasons for mving was the awful cable implementation of its TiVo rip-off. |
#228
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There are lots of DVRs out there, including freeware software that
runs on Linux boxes. (BTW, TiVo and Dish Network boxes are Linux boxes -- TiVo at one point was pretty open about how to get to the innards of their system.) You don't have to be married to the cable/TiVo DVRs. ....and so it will also be with radio, if anyone cares enough at this point. I personally don't think they'll care any more -- specific program listening will come through podcasts, and word of new media will spread via web pages, usenet and other BBS-like systems. When you can drop 100 hours onto a Flash card and put it in your portable MP3 player... no one cares or needs radio for entertainment any more. -- Eric F. Richards, "It's the Din of iBiquity." -- Frank Dresser |
#229
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Up yours,,,,,Blah blah blah,I knows me listener stuff. www.us963.com
Jacksonnnnnnn,,, where GOD isn't dead and 103.FM. Bite me! cuhulin |
#230
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I know the good stuff,and I dont need a stinking shotewave to get it
either.We are Mississippi Coon Asses around here. cuhulin |
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